1. Field of the Invention
The present invention deals with an integrated circuit for an electronic organ and, more particularly, to an I.sup.2 L circuit for superimposing audiofrequency electrical signals linearly, and to obtain them at certain outputs either as a voltage signal or as a current signal.
2. Description of the Prior Art
With the aid of master oscillators, voltage or current units may be formed and then superimposed. These units are not fixed absolutely in their amplitude, but may rise or drop to certain values either applied to or produced at the key contact, so that it is possible to achieve certain effects such as "sustain", "percussion", etc. Relative thereto, reference is made to the German technical journal "Funk-Technik" (1972), No. 19, pp. 695 to 699 and No. 20, pp. 737 to 784.
Superimposing the units of certain sound groups in accordance with the organizational scheme of the electronic organ, independently of the aforementioned possibilities of achieving special effects, should moreover be without interactions upon the amplitudes up to a maximum value. These interactions occur above all when actuating the keys and are noticed as a clicking noise ("bounce"), and are due to direct voltage or direct current steps, as has been described in the German technical journal "Funk-Technik" (1972), No. 17, pp. 630 to 632.